ITEM_AGED_TO_LOST events not cleared before synchronization

ITEM_AGED_TO_LOST needs to be deleted from the DB when synchronization starts:

1. entirely, in case of a full sync
2. for a particular patron, in case of a patron-level sync

Note: This issue affects all versions since 1.2.0 (when ITEM_AGED_TO_LOST event support was added) which includes Iris, Juniper, Kiwi.
However, in Kiwi these events are processed differently. In absence of ITEM_CHECKED_OUT event, ITEM_AGED_TO_LOST event won't result in a new openLoan record in userSummary, so not clearing these events from the DB before running a synchronization shouldn't affect user summaries and blocks. That said, it should be fixed anyway.